New York Yankees right-hander Masahiro Tanaka, who is currently rehabbing an injured right elbow, threw a bullpen session on Saturday and expressed confidence that his condition is improving to the extent he could be able to pitch in a game before his team's season ends Sept. 28.

The Japanese ace threw 34 pitches, mixing in his breaking balls. It was the first time Tanaka pitched since throwing a simulated game on Aug. 28, the day before the team shut his regimen down after he complained of general soreness in his right arm.

It was a positive sign for the 25-year-old Tanaka, who is trying to avoid Tommy John surgery after an MRI revealed a small tear in the ulnar collateral ligament of his right elbow.

"I feel confident that I am throwing with no problems. I have built a strong base, so I am able to put my strength into my pitching when I want to," Tanaka said.